Field of the Inventions
This application relates generally to climate control, and more specifically, to climate control of seating assemblies utilizing a thermoelectric circuit.
Description of the Related Art
Temperature modified air for environmental control of living or working space is typically provided to relatively extensive areas, such as entire buildings, selected offices, or suites of rooms within a building. In the case of vehicles, such as automobiles, the entire vehicle is typically cooled or heated as a unit. There are many situations, however, in which more selective or restrictive air temperature modification is desirable. For example, it is often desirable to provide individualized climate control for an occupant seat so that substantially instantaneous heating or cooling can be achieved. For example, an automotive vehicle exposed to the summer weather, especially where the vehicle has been parked in an unshaded area for a long period of time, can cause the vehicle seat to be very hot and uncomfortable for the occupant for some time after entering and using the vehicle, even with normal air conditioning. Furthermore, even with normal air-conditioning, on a hot day, the seat occupant's back and other pressure points may remain sweaty while seated. In the winter time, it may be desirable to quickly warm the seat of the occupant in order to enhance an occupant's comfort. This is particularly true where a typical vehicle heater is unlikely to quickly warm the vehicle's interior. For these and other reasons, there have long been various types of individualized climate control systems for vehicle seats. More recently, individualized climate control systems have been extended to beds, chairs, wheelchairs, other medical beds or chairs and the like.
Such climate control systems typically include a distribution system comprising a combination of channels and passages formed in one or more cushions of a seat. Climate conditioned air can be supplied to these channels and passages by using a climate controlled device. Climate conditioned air flows through the channels and passages to cool or heat the space adjacent the surface of the vehicle seat.
There are, however, problems that have been experienced with existing climate control systems. For example, some control systems utilize thermoelectric devices (TEDs) that can have a variety of configurations on the hot and main sides of the device. For configurations in which there is a heat exchanger on the main side with air flowing past it, condensation may form from water in the air. Whether or not condensation will occur and how much condensation will occur depends on the ambient air conditions (i.e. temperature and relative humidity) and the amount of temperature reduction from the inlet of the main side heat exchanger to the outlet. This condensation often can have undesirable consequences, from corrosion on metal parts to the creation of mold. Condensation may also partially or totally block airflow at the fin passages on the main side of the TED, resulting in reduction or loss of function.